Tolerance to self or foreign antigens is an active process that is mediated by multiple mechanisms. Central tolerance is promoted by negative selection or central deletion of a large number of lymphocytes capable of reacting to self molecules. However, some self-reactive lymphocytes remain to be regulated by active tolerance involving regulatory cells, anergy, or apoptosis. A breakdown in these mechanisms leads to autoimmune reactivity such as uveitis in the eye. The eye is an immune privileged site that has evolved to exhibit immune suppressive mechanisms that prevent immune inflammatory diseases in order to preserve vision. Anterior Chamber Associated Immune Deviation (ACAID) is a mouse model allowing for exploration of tolerance inducing mechanisms used by the eye. The role of lymphocytes associated with acquired immunity are well described in ACAID literature. These studies explore the mechanisms of regulation contributed by innate immune cells in the development of peripheral tolerance induced by antigen inoculation in the anterior chamber (ac). Building on results from studies in our first funding period we will explore the role of NKT cells in ACAID in sensitized mice, study how the antigen presenting cell (dendritic cell, DC) leads the NKT cell in the process of tolerance development and investigate the role of marginal zone (MZ) B cells in directing NKT cell function and ACAID. We will use cellular immunology methods, immunohistochemistry, molecular biology techniques (including rtPCR and Riboprobe analyses), flow cytometry, confocal microscopy and explore the potential genes involved by performing microgene analyses on genetic differences in 1) subsets of DCs, and 2) NKT cells exposed to tolerogenic APCs, versus MZ B cells. The results from these studies will generate better understanding of tolerance mechanisms in the eye and the individual as a whole. Mechanisms of tolerance induction in the sensitized animals may lead to novel therapies, potentially adaptable to patients with immune inflammatory diseases.